#include <wiringPi.h>
#include <stdio.h>
 
#define RelayPin      0
 
int main(void)
{
    if(wiringPiSetup() == -1){ //when initialize wiring failed,print messageto screen
        printf("setup wiringPi failed !");
        return 1; 
    }
//  printf("linker LedPin : GPIO %d(wiringPi pin)\n",VoicePin); //when initialize wiring successfully,print message to screen
     
    pinMode(RelayPin, OUTPUT);
 
    while(1){
            digitalWrite(RelayPin, LOW);            
            delay(1000);
            digitalWrite(RelayPin, HIGH);
            delay(1000);
    }
 
    return 0;
}